Grooving device



Sept. 24, w E ERRIG ET AL GROOVING DEVICE Filed Sept. 15, 1934 5 Sheets-Sheet 1 mm? Arromvzx pt 3 w. F. ERRIG ET AL- 2,015,635

GROOVING DEVICE v I Filed Sept. 13, 1934 5 Sheets-Sheet 2 Fl 6 4 g 74 v I i 4 4 72 7 I 7.9 4 .3

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GROOVING DEVICE Filed Sept. 13, 1934 5 Sheets-Sheet 3 Sept. 24, 1935. w, F E ET AL 2,015,"635

GROOVING DEVICE Filed Sept. 15, 1934 5 Sheets-Sheet 4 THE/A 19770671! nvvzwrami (01:76 MEiazdi,

Sept. 24, 1935. w. F. ERRIG ET AL GROOVING DEVICE Filed Sept. 13, 1934 5 Sheets-Sheet 5 nvvnvroxs. hillz'dm G' r e MHZ! g/$1.7M

1km nrromver Patented Sept. 24, 1935 UNITED STATES PATENT OFFICE GROOVING DEVICE Application September13, 1934, Serial No. 743,868

21 Claims.

. This invention relates in its broader aspects to grooving devices or machines more particularly adapted for cutting cross or otherwise directed grooves; or for trimming-up previously formed such grooves that have become reduced or worn and, consequently, more or less useless for their intended purposes.

More particularly this invention has reference to a cross-grooving device for grooving or regrooving worn and damaged rubber-tires of all types irrespective of whether they be solid, inflated or deflated.

More specifically the instant invention comprehends a grooving or re-grooving device characterized by novel means adapted to positively control the cutting of cross-grooves of any predetermined angularity evenly and in definite special relation. I

The primary object is to furnish a crossgroover which will out clean, regularly-spaced, angularly or otherwise directed cross-grooves of uniform depth and predetermined length; as well as being capable of manipulation to produce a practically unlimited variety of cross-groove designs and figures.

Another object is the provision of a crossgroover for re-cutting or trimmirg up worn tires, or for cross-grooving new tires of most conventional patterns and forms.

A further object is the provision of a groovingdevice for rubber-tires and analogous purposes which is capable of speedily cutting lateral and cross-grooves in a minimum of time, and incidentally, capable of transforming an old smooth tread tire into what resembles a brand new one.

A still further object of this invention is to provide a tire cross-groover which is comparatively simple and inexpensive to manufacture, positive and eiTective in action, and which lends itself readily for attachment to and cooperation with a machine of the type disclosed in prior Patent No. 1,916,258, granted to the present applicants under date of July 4, 1933.

Other and ancillary objects of this invention, kindred applications thereof, as well as the details of construction and operation whereby said invention may be practiced, will appear more fully hereinafter when considered in connection with the accompanying drawings; while it is to be particularly understood the subject-matter hereof is not confined to the exact features shown and described, various changes being readily made within the scope of the claims, without departure from the spirit of said invention, or as demanded by the prior art.

In all the views of the drawings corresponding parts are designated by similar reference characters.

Fig. I is a perspective view of a tire-groover of the type covered by prior Patent No. 1,916,258 with the cross-grooving attachment of the instant invention applied thereto.

Fig. H is a fragmentary plan view, and associated parts of the patented groover, showing the cross-groover of the present invention to a larger scale.

Fig. III is a side elevation thereof, or looking toward the right hand of the preceding illustration. I

Fig. IV is a detail plan view of the cutter supporting, direction-locating and adjusting means in one operative position.

Fig. V is a similar view showing the same parts in anotherposition.

Fig. VI is a detail view, to a larger scale, taken 2 approximately as indicated by the arrows VI-VI on Fig. VIII.

Fig. VII is a detail side elevation showing the cutter-operating lever and associated adjusting means. 5

Fig. VIII is an enlarged detail section taken as indicated by the arrows VIIIVIII on Fig. IV.

Fig. IX is a vertical section taken on the plane designated IXIX in Fig. IV.

Fig. X is a plan taken as indicated by the arrows X-X in Fig. VIII, and showing a movement limiting means in one position, as hereinafter explained. Fig. XI is a similar view showing the movement limiting means in another position. Fig. XII is a perspective view of a movement arrestor element later on fully described.

Fig. XIII is a perspective view of the cutter holder. t

Fig. XIV is a perspective view of the cutter. 40

Fig. is a plan view showing how the mechanism of Figs. IV and V may be positioned for cutting grooves at right angles to the tread 01 a tire, or paralleling the axis of said tire.

Fig. XVI is a detail side view of a racking means, later on fully described.

Fig. XVII is a side view, on a larger scale, showing the cutter operating means and carrier therefor in the inactive position.

Fig. XVIII is a similar view showing the same parts in the active or reverse position to that of the preceding illustration.

Fig. XIX is a fragmentary perspective view showing an example of the different cuts capable.

, or cross-grooving deflated tires; all of said mech-,

of being produced by the cross-cutter of this invention.

Fig. XX is a fragmentary elevation showing the angle-controlling means for cutting intersectory grooves in one position.

Fig. XXI is a corresponding view of the same means in another position.

Fig. XXII is a plan view of Fig. XXI and also indicating the position of 'an associated track member both in the position associated with said figure, as well as in dot-and-dash lines when the parts are related as shown in Fig. XX; and,

Fig. XXIII is an elevational view, taken on the plane designated XXIII in Fig. XV, or when the parts are located for cutting grooves directly crosswise of a tire or parallel with the axis thereof.

Referring first to Fig. I wherein the novel crossgroover forming the subject-matter of the instant invention is comprehensively designated by the letter A, the same is shown by way of example only as applied to a tire groover G, such as is described and claimed in the patent hereinbefore referred to. This patented tire groover G, briefly stated, includes a plurality of freely-rotative rollers one only being visible in the illustration, a spaced drive roller 2 on an operating shaft 3 journaled in brackets 4 on a vertically-adjustable cross-member or carriage 5, mounted between inverted Y-standards 6, said carriage being raised or lowered by means of screw-shaft I and hand-wheel 8, as described in the aforementioned patent; while 9 generally designates a universally-movable tire supporting shoe, for use when circumferentially grooving anism forming no part of the instant application and being merely referred to by way of better clarifying the present invention.

The cross-groover A comprises a rear element or bearer bar I9 which is adapted for rigid attachment as by bolts one only of which is visible in Fig. I, to the carriage 5 of the machine. Or, the bar l0 may be, obviously, otherwise mounted where convenient or desirable. Adjustable laterally of the bar Ill are a pair of supports |2 having clevised upper ends I3; while said supports are notched at H to engage over the upper edge of the bar l0, stud screws l5 at their lower ends serving to secure the supports |2 at the desired adjustment. Pivoted at 5 in the support clevises I3 is a channel-shaped support or hanger II, on the web portion l1 whereof is a holder member including an arm l8 afiording bearing for the operative parts of the cross-groover, while fulcrumed at l9, on one of the paralleling legs or side flanges of said hanger, is an inverted U-shaped, or other suitable, stop-member 20 adapted to engage or seat upon a contiguous part of the carriage 5, whereby the hanger 5 is disposed substantially-horizontal when in operative position. The holding arm l8, it will be seen, embodies a rear or claw portion l8 adapted to slidably engage the web portion ll of the hanger l1, and be secured rigidly thereto, at the desired adjustment laterally of the machine, by means of a lock-screw 2|; which said arm at its outer or opposed end embodies a slight elbow-portion 22; and said portion is vertically bored at 23 and counterbored at 24, for purposes later on explained, while its upper portion embodies circumferentially-spaced projections or angular stops 25, having downwardly-diverging edges 25' and 25". Axially of the borings 23, 24 is a fulcrum pin 26 having its lower end screw-threaded at 2'! into a lateral camming lug 28 of an arcuate arm or track 29, affording reciprocative support for the cutter mechanism, which will, also, be more fully described hereafter.

Referring again to the fulcrum pin 26 it will be best appreciated from Figs. IV, V, VIII and IX that it is formed with paralleling longitudinal flats 26 that afford axially-adjustable but non-rotative guidance for a sleeve 30 embodying diametrically-opposed projections 3|, having downwardly-convergent edges 3| for coaction with the elbow angular stop diverging edges 25 a and 25" as later on fully explained. As best seen in Fig. IX the lower end of the sleeve 30 is partially closed-in and diametrically grooved at 32, Fig. XII to afiord the non-rotative guidance relative to the fulcrum pin 26 above referred to, while a spring 33, seating in the elbow counterbore 241 and engaging a shouldered external-reduction 34, of said sleeve is maintained under compression by an adjusting wheel 35, threadedly engaged upon the upper end of the fulcrum pin 26, whereby the opposed projections 3| are limited, as regards rotary movement, between the elbow angular stops 25, as well as prevented from riding thereover.

Attention is, at this juncture, directed to the fact that intermediate the elbow stops 25, the elbow portion.22 of the arm I8 is grooved at 36 to receive a strong leaf-spring 31 secured therein by a set-screw 38; said spring embodying laminae of varying length and the longest 31' whereof coacts with cam edge of the lug 28 on the arcuate arm 29 above mentioned. The camming lug 28, it will be best seen from Fig. XI,-

is somewhat semi-oviform in contour so that as the spring 31 rides thereover it automatically snaps to the minor radial portion with respect to the axis of the fulcrum pin 26, under the limiting influence of the coasting projections 3| and angular stops 25. It is further to be particularly noted that opposed notches 39, Figs. III, XVII and XVIII, may be provided centrally intermediate the elbow angular stops 25, with which the sleeve projections 3| may be locked when it is desired to cut short or complete circumferentially-directed grooves in a tire, as later 0 more fully explained,

Referring now to the arcuate arm 29 aforesaid thesame is formed along its lower part with an offset or stepped-portion 40 which constitutes a guide or track for a long-and-short legged channel-section carriage, comprehensively designated 4|, said carriage being slidably-retained in position thereon by means of a bar or runner 42 rigidly secured by fastening means 42' to the top of the short leg of the carriage 4|, as clearly understandable from Fig. XVIII. Also from said figure it will be seen that the stepped-portion 40, of the arcuate arm 29, follows the curvature thereof; or, in other words, that the bar orv runner 42 traverses a path in parallel with the lower edge curvature of said arm. As illustrated the hereinbefore mentioned camming lug 28 is conveniently, although not essentially, formed as a lateral projection integral with the arcuate arm 29;. while the screw-threaded lower end 21 of the fulcrum pin 26 is immovably secured therein by a drift-pin 43 in an obvious manner.

The carriage 4|, is provided with a lateral projection 44 embodying downwardly-directed paralleling legs 45 with terminal-claws 46, jointly providing a shoe, and between which, the cutter carrier proper 41 is adjustably mounted.

' varied relativeto the shoe jointly afforded by the terminal claws 46. A spring 52 in compression seating in opposedly aligned sockets 53, 54, respectively provided for its reception, in the lateral projection 44 and the cutter carrier block 48 serves to not only maintain the cutter blade 55 fully projected relative to the shoe claws 46,

but also to.afiord .it a degree of give in the event of encountering some resistive element incorporated in the body or carcass of the tire being grooved, and thereby enhanching its durability, as well as obviating irregular depths of out under normal conditions. The cutter blade 55 is somewhat of the type disclosed in the prior patent hereinbefore mentioned in that it is of U-shaped section and is appropriately shaped for clamping attachment, as by a stove bolt 56, to the shouldered reduction 51 of the carrier block 48. It is, however, to be noted that the bolt 56 is located forwardly of the carrier block 48 and that the cutter blade 55 embodies parallel walls 58 with downwardly mergent portions 59 connected bythe cutter edge 59'. Location of the bolt 56 as just noted insures that the cutter ;edge 58' always shears into the tire being grooved. or re-grooved, with the upper edges of the walls 58 in firm engagement with the stepped parts 48' Fig. XIII of the carrier block 48.

Reciprocation of the cutter carriage 4|, is conveniently effected by means of a hand lever 80 having 'a forked angular end 6|, pivoted at 62 to-the outer or forward end of the arcuate arm 28, and a stepped coordinator member 53, pivoted at 54 to the hand lever 60 having a terminal extension 55, and at 56 to the outer carriage 4|.

Movement or throw" of the lever 60 is controlled by means of adjustable stop-screws 61, 51' engaged through correspondingly threaded lugs 58 projecting sidewise from said lever, such screws being ,adaptedto coact .with the upper and lower edges of the coordinator member extension 65, as hereafter explained; while set screws 69 serve to lock the stop screws 61 at the requisite adjustment for limiting the movement of the cutter carriage 4|, and consequently deter- .mally operated as described in the aforementioned prior patent. The ratchet handle 'embodies an apertured lug 13 through which threadedly engages an adjuster stop-screw 14, with a lock means 14, for coaction with the machine frame, as best shown in Fig. XVI to limit its movement in one direction or anticlockwise, while a stop projection 15 on the ratchet handle 1| limits movement in the reverse or clockwise direction. Carried by a lateral projection 16 on the handle II is a springy racking-tongue or ,ciated set screw 69.

detent 11 for coaction with the ratchet wheel 12 in an obvious manner; while a trip 18 fulcrumed at 19 to the projection 16 serves to rigidly hold the tongue 11 in position for racking the ratchet wheel I2, or to release or disengage it from coaction with the ratchet wheel teeth, when operating the groover G for cutting circumferential grooves around a tire.

In operating the novel cross-grooving attachment A and assuming that a wheel 80 (Fig. I) with an inflated worn tire T has been duly positioned or set on the groover G for re-cutting of the worn down cross grooves; the operator just slackens the lock screw 2| and locates the cutter blade 55 and carrier 4'! directly in alignment below the adjusting wheel 35 and fulcrum pin 26, by drawing the hand lever 6|] forwardly from the full line showing in Fig. VII, to the associated dot-and-dash line position in the same View, and sliding the entire. attachment A" crosswise along the hanger web position until the cutter 55 is exactly central of the tire T, whereupon the lock screw 2| is retightened up, and the adjustable screw 61 secured by its asso- The hand lever 6|] is next moved back to the'full-line position of Fig. VII and the parts 60, 63 and 29 swung to the right or counterclockwise, as shown in Figs. II and IV, whereupon the adjustable screw 6'! is manipulated until the cutter blade 55 is in the desired position at the left of the tire T for commencing a diagonal-cut 8| Fig. II, whereupon said screw 61' is locked by its associated set-screw 69. Thus the screws 61, 61' determine the travel of the cutter carriage 4|, and consequently the length of the cross groove 8| cut. The parts 60,

63 and 29 are now swung to the left or clock-.

wise about the fulcrum pin 26 to the position shown in Fig. V to cut an intersecting cross groove 82 from right to left of the tire T in the man-- ner above described. In order to regulate or determine the circumferential spacing of the cross-grooves 8|, 82, around the tire T the operator simply manipulates the stop-screw 14, carried by the ratchet handle 1|, to determine how many teeth of the ratchet I2 the rackingtongue shall ride over within the limits of movement prescribed for said handle 1|, and as predetermined by contact of the end of the screw 14, and the handle projection 15 with the machine framework, as hereinbefore set forth. The depth of the grooves 8 82 cut is determined by appropriate manipulation of. the knurled-nut 5|; while to throw the groove-spacing mechanism out of action the operator simply raises the trip lever 18 which moves the racking-tongue l1 outwardly from the province of the ratchet wheel 12 in an obvious manner. It is to be noted that when cutting diagonally-intersecting or grooves, such as 8|, 82, both angular cuts should be made without moving the tire T by the racking handle II; or, at the end of cutting the first groove 8|, for example, the operator should raise the cutter 55 and associated mechanism on the hanger pivots l6, and. swing the attachment A about the fulcrum 26 into position for cutting the intersecting groove 82.

It is also to be particularly noted that angular stops 25 are so spaced that, by coaction of their inner inclined or divergent faces 25' with the converging faces 3| of the sleeve opposed projections 3|, the degree of angularity of the cross grooves 8|, 82 is varied. This feature will be best understood from Figs. XX and XXI where.- in location of the projection 3|, by manipulation of the adjusting wheel, in the former figure at the upper position relative to and for coaction with the top portions of the angular stops 25 determines the maximum arcuate swing. of the track arm 2|. Contrariwise when the projection 3| is at the low position shown by Fig. XXI it will be equally apparent that the track arm 2| will swing over an arc of much less extent. Or, in other words, Fig. XX indicates the position of the parts 36, 3| and 22, 25 when the attachment A is adjusted for cutting grooves 8| 82 of amaximum degree of relative angularity; while Fig. XXI indicates the position of said parts when adjusted for effecting cross groovings of a minimum degree of relative angularity. In Fig. XXII the full line position of the arcuate arm and track 29, 4B the directional travel of the cutter for making cross-grooves of minimum relative angularity; and the dot-and-dash line position that for cutting cross-grooves of maximum relative angularity. Obviously positioning of the sleeve projection 3| at any level intermediate the showings of Figs. XX and XXI will effect a corresponding variable throw or swing for the arcuate arm 29.

It is also to be especially remarked that when right-angle grooves, such as shown at 83, (Fig. XIX) are desired, directly across the width of the tire T, the operator simply slackens the ad-' juster wheel 35 sufiiciently to position the sleeve opposed projections 3| at the back or in contact with the faces 25" of the angular stops 25, as best understood from Figs. XV and XXIII, when the arcuate arm 29 and track 40 occupy a position directly across the tire T or paralleling the rotational axis of said tire.

Somewhat similarly when the sleeve projections 3| are forced down into the locking notches 39, which Will position the arcuate arm 29 in registration with the periphery of the tire T, short circumferential cuts such as 84, Fig. IHX may be cut intermediate alternate pairs of the crossgrooves 83, by appropriate manipulation of the spacer ratchet handle II; or, complete circumferential grooves may be cut bythrowing ratchet handle ll out of action, as hereinbefore explained, and manipulating the attachment by the operating handle 70, with the parts 60, 63 and 29 held I stationary and in line with the tire circumferentially.

From the foregoing description it will be apparent that the illustrated form of this invention herein disclosed is well calculated to adequately fulfill all of the various objects set forth, and it will be equally evident that many strucframe, a holder member on the frame, a reciprocative cutter-bearing element pivotally carried by the holder member, and angular stops on the holder member, and radial projections axially adjustable of the bearing element, said stops and radial projections having inclined coactive slopes for variably regulating and limiting the swing of the cutter-bearing element, and also for locking said element in a definite 'diametric direction.

2. In a tire cross-groover the combination of a frame, a holder member on the frame, a reciprocative cutter-carrier vertically fulcrumed to 5 the holder member, angular stops on the holder member circumferentially-spaced relative to the vertical fulcrum, and axially-adjustable projections on the fulcrum axis coactive with a pair v of the confronting inclined faces of the angular 10' stops to variably control the pivotal swing of the cutter-carrier, said projections when moved into engagement with the opposing pair of the angular stops confining movement of said carrier to a path at right angles to the rotative plane of 15- the tire.

3. In a tire cross-groover the combination of a frame, a holder member on the frame, a cuttercarrier slidable over an arcuate track, said track 7 being vertically pivoted to the holder member, 20 circumferentially-spaced angular stops on the holder member about the vertical pivot, a springinfluenced sleeve on said pivot having diametrically opposed projections, and adjuster means I whereby, when one of said projections is posi- 25 tioned for coaction with one pair of the stop contiguous faces the cutter-carrier is confined to a variable arcuate movement, and when both of the sleeve projections are positioned against the v other pair of stop circumferentially-opposing 30- faces the cutter-carrier is restricted to movement at right angles to the rotative planeof the tire.

4. In a tire cross-groover, a frame, a vertically swingable support on the frame, a holder mem- 35 ber adjustable horizontally of said support, a

,track pivotally sustained by the holder member,

' a frame, a vertically swingable support on the frame, said support including means whereby it is attachable to a rigid structure and, means to hold said support in a horizontal position, a hold- 50 3 er member adjustable laterally of said support,

a track vertically pivoted to the free end of the holder member, a cutter bearing carriage slidable along the track, and means whereby the carriage is reciprocable between controllable limits in op-v 55 posing angular directions to effect cutting of intersecting cross gro'oves.

6. The combination of claim 5 wherein the vertically swingable support comprises a substantially channel-shaped element with pendent members pivoted at its ends, said pendent mem-' bers having means for securing the same to a rigid structure.

'7. The combination of claim ,5 wherein the holder member is formed with a claw portion to slidably engage the vertically swingable support, and means whereby said claw portion may be clamped to the support at the desired lateral adjustment. 4*

8. The combination of claim 5 wherein the swingable support includes an inverted pivotal U-shaped stop for coaction with a rigid structure to maintain said support in horizontal position. i

9. In a tire cross-groover the combination of a frame, a vertically swingable supporton the frame, said support including means whereby it is attachable to a rigid structure and means to hold said support horizontal, a holder member adjustable laterally along the swingable support, said member embodying a vertically aperturedportion at its free end, a track pivotally sustained by the apertured portion with a cam means restraining rotation thereof, a. cutter bearing carriage slidable along the track, and means whereby the carriage is reciprocable between controllable limits in opposing angular directions to effect cutting of intersecting cross grooves.

10. In a tire cross-groover the combination of a frame, a vertically swingable support on the frame, said support including means whereby it is attachable to a rigid structure and means to hold said support horizontal, a holder member adjustable laterally along the swingable support, said member embodying a vertically aperturedelbow with an upper counterboring at its free end, a track with a fulcrum pin journaled in said elbow, means carried by the fulcrum for coaction with vertical projections on the elbow to limit arcuate travel of the track aforesaid, a cutter bearing carriage slidable along the track, and means whereby the carriage is reciprocable between controllable limits in opposing angular directions to efiect cutting of intersecting cross grooves.

11. The combination of claim 10 wherein the fulcrum pin is rigidly secured in a lateral lug integral with the track, said lug having a camming edge for movement restraining coaction with a leaf spring secured to the holder member elbow portion.

12. The combination of claim 10 wherein the holder member is provided with angular stops at its upper end, and the fulcrum pin carries an axially adjustable non-rotative sleeve having diametric projections for coaction with the angular stops to variably limit arcuate travel of the track.

13. In a tire cross-groover the combination of a frame, a vertically swingable support on the frame, said support including means whereby it is attachable to a rigid structure and means to hold said support horizontal, a holder member adjustable laterally along the swingable support, said member embodying a vertically apertured elbow at its free end with an upper counterbore, a track with a lateral lug having a camming edge for coaction with a pendent leaf spring on said elbow, said lug having a fulcrum pin with.opposing longitudinal flats and being journaled in the holder member apertured elbow, angular stop projections at the upper end of the elbow, a sleeve having a diametrically grooved end for coaction with the fulcrum pinflats to prevent its rotation, said sleeve having opposed projections for coaction with the elbow projections to variably limit arcuate travel of the track, a spring in compression intermediate the holder member elbow counterbore and the sleeve, an adjusting wheel threadedly engaging the upper end of the fulcrum pin to vary the lateral swing of the track, a cutter bearing carriage supported by the track, and means whereby said carriage is reciprocable in opposing angular directions to effect cutting of intersecting cross grooves.

14. The combination of claim 13 wherein the track lateral lug is semi-oviform in contour, the fulcrum pin threadedly engages therein and is locked against movementby a drift pin, and the coacting leaf spring is secured in a vertical groove in the holder member elbow portion.

15. The combination of claim 13 wherein the holder member elbow portion is provided with diametric notches in its upper face, and the sleeve opposed projections are adapted to be forced into said notches by the fulcrum pin adjuster wheel to 5 look the track in line with the tire toefiect cir- I cumferential grooving,

16. In a tire cross-groover the combination of a frameQa vertically swingable hanger-support on the frame, a holder member adjustable later- 1 ally of said support and having a vertically apertured elbow at its free end, a longitudinallycurved track with an offset fulcrum pin journaled in said elbow, a spring influenced sleeve nonrotatively mounted on the fulcrum pin and hav- 15 ing opposed projections for variable coaction with angular stops on the elbow aforesaid, means whereby said sleeve may be adjusted to vary the arcuate travel of the track, a cutter bearing carriage on the curved track, and lever means coordinating the carriage and track for predetermined lateral and reciprocative movement respectively to effect alternate cutting in opposing angular directions of intersecting cross grooves.

17. The combination of claim 16 wherein the longitudinally curved track is of stepped crosssection, the cutter bearing carriage is formed of long-and-short leg cross section, and said short leg portion is fitted with a runner for sliding engagement along the track stepped portion. 18. The combination of claim 16 wherein the cutter bearing carriage is provided with an offset embodying spaced shoe portions, and the cutter is supported by a block vertically adjustable between said shoe portions. 19. The combination of claim 16 wherein the cutter is carried by a block between spaced pendent shoe portions of the carriage, said block having a vertical support with an adjusting nut threadedly engaging its upper end, and the block'40 is influenced by aspring in compression housed in axially aligned sockets in said block and the carriage.

20. In a tire cross-groover the combination of a frame, a vertically swingable hanger-support on the frame, a holder member adjustable laterally of said support and having a vertically apertured elbow at its free end, a longitudinallycurved track with an offset fulcrum pin journaled in said elbow, a spring influenced sleeve nonrotatively mounted on the fulcrum pin and having opposed projections for variable coaction with angular stops on the elbow aforesaid, means whereby said sleeve may be adjusted to vary the arcuate travel of the track, a cutter bearing carriage on the curved track, an operating lever pivoted to the forward end of the track, a coordinating link fulcrumed at one end to the cutter bearing carriage and pivotally connected to the operating lever intermediate its ends with projection beyond such pivotal connection, and means coacting with the link projecting portion for limiting movement of the operating lever.

21. The combination of claim 20 wherein the coordinating link is longitudinally stepped, the operating lever is provided with lateral apertured lugs having adjustable stop screws passing therethrough, and means are provided for locking 7 said screws at the desired adjustment for limiting movement of the operating lever.

WILLIAM F. ERRIG. [1... 5.] GEORGE M. PFUNDT. [1. 5.] 

